docs: def sample(self, sample_size=20):
          """
          This method retrieve an iterable object that implements the method
          __iter__. The arguments given will compose the parameters in the
          request url.
  
          kwargs: sample_size (Integer) between 0 and 100.
  
          return: iterable object of Works metadata
  
          Example:
              >>> from crossref.restful import Works
              >>> works = Works()
              >>> works.sample(2).url
              'https://api.crossref.org/works?sample=2'
              >>> [i['title'] for i in works.sample(2)]
              [['A study on the hemolytic properties ofPrevotella nigrescens'],
              ['The geometry and the radial breathing mode of carbon nanotubes: beyond the ideal behaviour']]
          """
          context = str(self.context)
          request_url = build_url_endpoint(self.ENDPOINT, context)
          request_params = dict(self.request_params)
  
          try:
              if sample_size > 100:
                  raise UrlSyntaxError(
                      'Integer specified as %s but must be a positive integer less than or equal to 100.' % str(sample_size)
                  )
          except TypeError:
              raise UrlSyntaxError(
                  'Integer specified as %s but must be a positive integer less than or equal to 100.' % str(sample_size)
              )
  
          request_params['sample'] = sample_size
  
          return self.__class__(request_url, request_params, context, self.etiquette)